1. Field of the Invention
This invention concerns the use of a particular rust inhibitor to inhibit rust formation in lubricating oils formulated from highly saturated base oils.
2. Description of Related Art
Many lubricating oils require the presence of rust inhibitors to inhibit or prevent rust formation, which often occurs due to water contacting a metal surface. Until now, the industry has assumed that all commercially available rust inhibitors are capable of protecting a metal surface from water. However, rust inhibitors presently available in the marketplace were developed for conventionally processed basestocks that contain significant amounts of aromatic and polar compounds and relatively small amounts of saturates.
Surprisingly, we have found that most commercially available rust inhibitors are ineffective in preventing rust in lubricating oils formulated from highly saturated basestocks.